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Published on: January 17, 2016
Expression of Fgf19 in the developing chick eye
Javier Francisco-Morcillo1, Hortensia Sánchez-Calderón, Yasuhiko Kawakami
1Departamento de Biología Celular, Facultad de Veterinaria, Universidad de Extremadura, Avda. de la Universidad s/n, 10071 Cáceres, Spain. morcillo@unex.es
Insights
Fibroblast growth factor 19 (FGF19) mRNA is transiently expressed in developing chick retinal neuroblasts and horizontal cells. FGF19 expression in the retina and lens is limited to embryonic stages, decreasing by postnatal day 30.
Area of Science:
- Developmental biology
- Ophthalmology
- Molecular biology
Background:
- Fibroblast growth factor 19 (FGF19) is a recently identified member of the FGF family.
- FGFs play crucial roles in embryonic development, cell proliferation, differentiation, and migration.
Purpose of the Study:
- To investigate the spatiotemporal expression pattern of Fgf19 mRNA in the developing chick retina and lens.
- To determine the cellular localization and developmental timing of Fgf19 expression.
Main Methods:
- In situ hybridization to detect Fgf19 mRNA localization.
- Immunohistochemistry using Pax6 antibody to identify cell types.
- Analysis across multiple developmental stages from Hamburger and Hamilton stage 15 (HH15) to postnatal day 30 (P30).
Main Results:
- Fgf19 mRNA was transiently detected in postmitotic neuroblasts during their migration in the developing retina.
- From embryonic day 7 (E7) onwards, Fgf19 expressing cells, identified as Pax6-positive horizontal cells, were located in the outer region of the presumptive inner nuclear layer.
- Fgf19 expression in the retina decreased during late embryogenesis and was undetectable by P30.
- Transient Fgf19 expression was also observed in the equatorial region of the developing lens.
Conclusions:
- FGF19 exhibits a transient expression pattern during critical phases of chick eye development.
- FGF19 is expressed in specific neuronal populations, including migrating neuroblasts and horizontal cells in the retina.
- The developmental expression profile suggests a potential role for FGF19 in retinal and lens development, with its expression diminishing postnatally.
Abstract:
Fibroblast growth factor 19 (FGF19) is a new member of the FGF family of growth factors. Here, we describe the localization of Fgf19 mRNA in the developing chick retina and lens in stages from the Hamburger and Hamilton stage 15 (HH15) to postnatal day 30 (P30). Fgf19 was expressed in a transient manner in postmitotic neuroblasts during the migration from the ventricular surface to their final location. Moreover, from HH31 (embryonic day 7, E7) on, a subset of lined up Fgf19 expressing cells was distributed in the outer region of the presumptive INL. These cells were Pax6 immunoreactive horizontal cells. During the last third of embryogenesis, Fgf19 expression in the retina was progressively down-regulated and was not detected at P30. Also, it was transiently expressed in the equatorial region of the lens.
